Different wood, different polishing techniques

General polishing steps

Grind for a smooth surface: For efficient grinding of boards, use a combination of machine and hand techniques to grind from low to high.

Start with power tools and eliminate machine marks: With a 5- to 6-inch diameter disc sander, grind from 150 mesh to 180 mesh. When using the sander, a padded glove will be worn to reduce the vibration of machine operation.

Finish with hand sanding: After machine sanding to 180 mesh, wrap 220 mesh sandpaper around a cork sanding block and continue with hand sanding. The carpenter’s master may berate you if you don’t follow the grain direction when sanding, but sanding at an Angle of 7° to 10° from the grain direction will remove the fibers better and will not leave significant lateral scratches on the surface of the wood.

Hand sanding board: If you feel tired of holding on to sand blocks for a long time, you can use the hand sanding board with Velcro as shown in the picture. It is much easier to use.

Grinding end: It is usually finished after grinding the grain surface to 220 mesh, but the horizontal grain surface still needs to continue grinding until about 400 mesh, so as to achieve a smooth surface effect like glass.

Smooth out large sheets

For more than 20 years, Jeff has been answering questions about woodworking and finishing, and one of the most vexing questions he’s ever asked is what to do with a large board to get a flat surface.

Large boards are often too wide to pass the planing, hand planing skills are not up to par, and the 5-inch disc sander at hand is too small to polish evenly.

Jeff’s solution was to use a belt sander. Two 11⁄ 2-inch strips of wood are clamped up and down at both ends and in the middle of the board surface with clamps. The clamps are tightened evenly and the board is pressed as flat as possible by the pressure exerted by the clamps.

Jeff will use a thin sheet to scrape off excess glue, but the sealing tape will do as well. Then evenly tighten the steel rod clamp, and use a rubber hammer to hit the boards around the seam, as far as possible to make the boards flush with each other.

First up and down clamp, and then around clamp: first of all, before and after the board and the middle of the upper and lower clamp on the wood, tighten the clamping fixture up and down, exert pressure on the wood, rely on the restriction of the wood clipboard flat. Then evenly tighten the clamp in the left and right directions of the board in order to make the board more tightly glued.

Despite these precautions, there is usually some unevenness between the panels, which requires some heavy equipment. The first choice of 4*24 inches of large sanding machine, followed by 6 inches of diameter disc sanding machine, whether cylindrical grip or gun grip can be, although the efficiency is low, the effect is not bad, but the premise is that your tool quality to pass.

Grind in different directions to achieve a flat cutting effect

Crossline grinding method: The best way to smooth the bonding area between the boards is to grind the grinder evenly from left to right at an Angle of 45° with the grain direction.

Then continue grinding from right to left at a 45° Angle.

Polish along with the texture: when the gluing parts of the board are ground flat, polish the whole board along with the texture of the board.

Check progress: Use a level longer than the width of the panel to check for any overhead on the table. When the level shows the level of water on each part of the table, you can start the next step of polishing.

Grinding of narrow parts

Small step splicing Angle: make a special grinding block that can be just polished to the step without causing transverse wear to the wood. Paste pressure-sensitive adhesive sandpaper on the woodblock or use glue spray to paste ordinary sandpaper on the woodblock for grinding.

Narrow parts overturn balance: The sander can easily tilt to one side when sanding a narrow surface, causing the Angle of the wood edge to be worn away.

Grinding several narrow parts together not only provides a more stable surface but also speeds up the grinding process.

Inspection of grinding effect

The side light will make uneven areas on the board visible. Use a low-angle light source to illuminate one side of the panel to the other to see if the panel is flat.